1. Field of the Invention
This invention relates generally to a container tracking system. More particularly, it relates to an apparatus and technique for allowing a shipping container to disburse sensor information through a network formed with other shipping containers.
2. Background of Related Art
Terrorism has brought the reality of threats outside of the United States possibly shipping hazardous substances such as biological, radioactive waste, nuclear, chemical, etc. into the United States for use in a terrorist act. Such possibilities have resulted in a need for increased security relating to shipping containers.
The U.S.'s maritime borders include 95,000 miles of open shoreline, and 361 ports. The U.S. relies on ocean transportation for 95 percent of cargo tonnage that moves in and out of the country. Each year more than 7,500 commercial vessels make approximately 51,000 port calls, and over six million loaded shipping containers enter U.S. ports. Current growth predictions indicate that container cargo will quadruple in the next twenty years.
FIG. 9 illustrates a conventional cargo hazard detection system for a package 900 within a truck 901.
The conventional cargo hazard detection system for a package 900 within a truck 901, includes a package hazard sensor 902, a satellite communications transmitter 903, a communications satellite 904, and a central database 908.
A package hazard sensor 902 monitors for potential hazards within the package 900 and transmits an alarm signal to the satellite communications transmitter 903.
The package hazard sensor 902 relies on radio frequency signal reflection or infrared light signal reflection to transmit its information to a satellite communications transmitter 903 attached to the top of the truck 901.
Once a determination is made that a potential hazardous substance inside of the package 900 has been detected by the package hazard sensor 902 the hazard signal is transmitted to the communications satellite 904. The communications satellite 904 relays the hazard signal produced by the hazard sensor 902 to the central database 908.
A user at the central database 908 is alerted as to the existence of the hazard signal and responds appropriately according to the type of hazard detected. For instance, if the hazard is a chemical leak, a chemical clean-up team is sent to investigate the shipping container and respond accordingly.
Thus, the prior art requires either signal reflection, using RF transmissions, or a line of sight using infrared transmissions, for a hazard sensor to relay its information to a central database.
FIG. 10 illustrates a conventional cargo ship.
The conventional cargo ship 1001 carries a plurality of conventional shipping containers 1002. The plurality of conventional shipping containers 1002 are placed within various parts of the ship 1001. Some of the conventional shipping containers 1002 are at the top of a stack 1003 of conventional shipping containers 1002. Some of the shipping containers are at the bottom of a stack 1004 of conventional shipping containers 1002.
On the conventional cargo ship 1001, there is a lack of sensors for determining potential hazards within the conventional cargo containers 1002.
Accordingly, there is a need to sense hazards aboard cargo ships before the cargo is placed on trucks for delivery. Moreover, there is a need to transmit sensor information from a shipping container when the shipping container is stacked underneath a plurality of other shipping containers. Moreover, there is a need to be able to transmit sensor information from a shipping container over a plurality of communication paths in the event that one of the communication paths is unavailable.